the begginning

utils/testbc/fileblockrequestqueue.cpp

@@ -0,0 +1,89 @@
+/* Copyright (C) 2014 InfiniDB, Inc.
+
+   This program is free software; you can redistribute it and/or
+   modify it under the terms of the GNU General Public License
+   as published by the Free Software Foundation; version 2 of
+   the License.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program; if not, write to the Free Software
+   Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
+   MA 02110-1301, USA. */
+
+/***************************************************************************
+ *
+ *   $Id: fileblockrequestqueue.cpp 666 2008-07-22 14:39:46Z wweeks $
+ *
+ *   jrodriguez@calpont.com   *
+ *                                                                         *
+ ***************************************************************************/
+
+
+#include "fileblockrequestqueue.h"
+
+using namespace std;
+
+namespace dbbc {
+
+
+fileBlockRequestQueue::fileBlockRequestQueue() : queueSize(0), readersWaiting(0)
+{
+	pthread_mutex_init(&mutex, NULL);
+	pthread_cond_init(&notEmpty, NULL);
+}
+
+fileBlockRequestQueue::~fileBlockRequestQueue()
+{
+	pthread_cond_destroy(&notEmpty);
+	pthread_mutex_destroy(&mutex);
+}
+
+bool fileBlockRequestQueue::empty() const
+{
+	return (queueSize == 0);
+}
+
+fileRequest* fileBlockRequestQueue::top() const
+{
+	return fbQueue.front();
+}
+
+int fileBlockRequestQueue::push(fileRequest& blk) {
+	pthread_mutex_lock(&mutex);
+	fbQueue.push_back(&blk);
+
+        // @bug 1007.  Changed "== 1" to ">= 1" below.  The wake up call was only being fired when the queue size was 1 which
+        // caused only one i/o thread to be working at a time. 
+	if (++queueSize >= 1 && readersWaiting > 0) 
+		pthread_cond_signal(&notEmpty);
+	pthread_mutex_unlock(&mutex);
+	
+	return 0;
+}
+
+void fileBlockRequestQueue::stop() {
+	pthread_cond_broadcast(&notEmpty);
+}
+
+
+fileRequest* fileBlockRequestQueue::pop(void) {
+	pthread_mutex_lock(&mutex);
+	while (queueSize == 0) {
+		readersWaiting++;
+		pthread_cond_wait(&notEmpty, &mutex);
+		readersWaiting--;
+	}
+
+ 	fileRequest* blk = fbQueue.front();
+ 	fbQueue.pop_front();
+	--queueSize;
+	pthread_mutex_unlock(&mutex);
+	return blk;
+}
+
+}